Operator scheduling approaches in group technology cells-information request analysis

This paper examines the group technology (GT) scheduling problems, in which each cell is staffed with one operator. The role of the operator is to load jobs into machines, to unload jobs from machines, and to transport jobs between machines. Since the productivity of the cell is directly proportional to the level of productive work performed by the operator, the manner in which the operator moves between machines affects productivity. Although the optimal operator schedule/walking-pattern has been shown to be the best operator schedule for well-structured production environments, the underlying assumptions of the optimal schedule often limit its practical implications. With the current popularity of gust-in-time production, the problem of finding an efficient operator schedule/walking-pattern has become a critical issue in shop floor scheduling. According to the information requirements, this paper devises three heuristic approaches: a scheduling rule, multiple scheduling rules (MSR), and cycle switching rules (CSR). This paper shows that there is a tradeoff between the quality of the resulting schedule and the information contents of heuristics used